Baffle type muffler



Dec. 22, 1953 w. KELLER BAFFLE TYPE MUFFLER Filed Dec. 11. 1950 William Keller INVENTOR WWW ATTORNEY Patented Dec. 22, 1953 UNITED STATES PATENT OFFICE 'BAFFLE TYPE MUFFLER William Keller, Flint, Mich. Application December 11, 1950, Serial No. 200,216

2 Claims. 1

The present invention relates to mufflers and more particularly to mufiiers of the type commonly used in the exhaust systems of internal combustion engines.

The principal object of the invention is to provide a novel and improved muffier which will render the maximum silencing effect with the minimum amount of back pressure.

Another object of the, invention is to provide a mufiier which can be manufactured in mass production with the fewest number of differently shaped parts and one that can be assembled without the use of complicated fixtures and jigs for properly spacing and supporting the elements at their locations relative to one another during the attachment thereof together.

A further object of the invention is to provide a muiiier as set forth in the preceding oblects wherein identical bafiles of a unique construction are associated in reverse positions relative to the baflies adjacent thereto for-producing alternate size and shaped chambers and which will cause a helical motion of the exhaust gases in a single direction while passing through openings in the baffles, said openings in each baffle being of a size equivalent to the area'of the entrance opening to the-mufl'ler.

It is also an object of the invention to provide a muflier of the above-indicated character which is simple and substantial in construction, economical to manufacture, and thoroughly eflicient and practical in use.

These, together with various auxiliary features and objects of the invention which will later become apparent as the following description proceeds, areattained by the present invention, a preferred embodiment of which has been illustrated, by way of example only, in the accompanying drawings, wherein:

Figure 1 is a central longitudinal section through the improved muflier, showing some of the bailies in elevation and others in section;

Figure 2 is a cross section taken on line 2-4 of Figure 1; and

Figure 3 is a diagrammatic view, illustrating in full and dotted lines the helical motion of exhaust gases while passing through the muffler.

Referring now more specifically to the accompanying drawings, wherein like numerals designate similar parts throughout the various views, the numeral indicates a tubular casing which has attached to the opposite ends thereof, by welding or any other approved method, closure members H and I2 with flanged inlet and outlet openings l3 and M, respectively. The flange of the inlet opening l3 is adapted to be connected to the exhaust pipe leading from an engine, while the flange of the outlet opening I4 is forconnection to thepipe'from which the exhaust gases are discharged to the atmosphere. Both enclosure members H and I2 are preferably formed to the same size and shape for minimizing the number of parts of different construction.

Within the tubular casing "10 is arranged a number of identically constructed circular cross walls in the form of baflies I5, there being six shown for the purpose of illustration. Each bafiie consists of a substantially cone-shaped wall I 6 having a plurality of spaced'louvers l'l formed therein and a cylindrical flange "I8 formed at the periphery or base'of said wallof a size whereby the outer surface of said flange snugly engages the inner surface of the tubular casing Hi. The louvers H in each baffle are likewise identical andare preferably of a=number and opening size equal to the area of the opening 13 through which exhaust gases enter-the mu'iiler for reducing back pressure. Also, all louvers I! of each baflle extend radially froma location near the apex IQ of the bellied cone-shaped wall 16 to a location adjacent thecylindrical' flange I 8, and all are formed so that the'angle'of the walls of the louvers at their openings directs gases passing therethrough'in a-helical-direction.

As shown in Figure 1; the identical'bafiies I5 are so constructed that reversing the positions of adjacent bafiies in "the casing by first contacting their apexes i9 and-then the edges of their cylindrical'flanges' [8 provides alternate size and shaped expansion chambers 20 and 21 between the different baflies, and gases passing through all battles are directed in the same helical direction. All of the flanges l8 of the baffies l5 or, if desired, only the flanges of the end baflies are attached to the casing 10 by spot welding for holding the baffles in proper position in the casing and for providing end gas expansion chambers 22 and 23 forwardly and rearwardly of the bafiles. Abutting apexes of adjacent baffles may also be welded together if so desired.

The diagrammatic illustration, Figure 3, shows with fulland dotted-line arrows 24 and 25 the generally helical direction of the flow of exhaust gases through the mufller, and indicates by the directions of the arrows alternate size gas expansion chambers through which the gases pass.

In operation, the exhaust gases enter the muffler through the flanged opening I3 and are free to expand to a certain extent in the chamber 22 after which they pass through the openings in the louvers I! of the first baffle 15 and are directed in a whirling motion by the angles of the 'walls of the louvers as they enter the first smaller annular expansion chamber 29 enclosed by the wall of the tubular casing 10. Due to continuous pressure on the gases, they enter through the louver openings in the second of the baffles I5 and are started in a helical direction into a larger substantially circular expansion chamber 2| formed by abutting flanges of the second and third bafiies l5. This procedure through alternate size and shaped chambers is followed throughout the travel of the gases past the baffles 15 until the gases enter the rear exthis art. A more detailed description is accordingly deemed unnecessary.

It is to be understood, however, that even though there is herein shown and described a preferred embodiment of the invention, various changes may be made without departing from the spirit and full intendment of the invention.

What is claimed is:

1. A mufiler comprising a tubular casing having an inlet opening at one end and an outlet opening at the other end; a baffle in said casing adjacent one end thereof and consisting of a circular plate bellied by having the central portion thereof laterally ofiset toward one end of the tubular casing and having radially extending openings therein that are louvered outwardly from the convex side of said bellied portion in a manner to spirally deflect gases passing through the openings, and a cylindrical flange at the periphery of said circular plate concentric to said tubular casing and extending in a direction opposite to that of said bellied ofiset portion, said cylindrical flangebeing in engagement with and secured to the inside of the tubular casing; a plurality of other baflies of identical construction to that of said first-mentioned bafile positioned in said tubular casing between said firstmentioned baffle and the opposite end of the tubular casing with the flanged portions and offset bellied portions alternately reversed relative to one another and to the flanged portion and bellied portion of said first-mentioned baifie thereby arranging the louvered openings of all of said bafiies in directions to produce a continuous helical motion to gases passing under pressure through the tubular casing; and means supporting said plurality of bafiles in said casing with their flange portions and ofiset bellied portions in abutting engagement with like portions of adjacent baffles.

2. A mufiler comprising a tubular casing having an inlet opening at one end and an outlet opening at the other end; a baflie in said casing adjacent one end thereof and consisting of a circular plate bellied by having the central portion thereof laterally offset toward an end of the tubular casing and having radially extending openings therein that are louvered for spirally deflecting gases passing through the openings, and a cylindrical flange at the periphery of said circular plate concentric to said tubular casing and extending in a direction opposite to that of said bellied offset portion, said cylindrical flange being in engagement with the inside of the tubular casing and secured to said casing; a plurality of other ballies constructed in a like manner to that of said first-mentioned bafile and packed in said tubular casing against said first-mentioned baiile with their flanged portions and offset bellied portions alternately reversed relative to one another and to the flanged portion and oiiset bellied portion of said first-mentioned bafile, said flanged portions and offset bellied portions being in abutting engagement with like portions of adjacent bafiies; and means securing the flange of the baiile of said plurality of bafiies that is furthest remote from said first-mentioned bafile to the tubular casing and thereby support all bafiles of said plurality of bafiies relative to one another and to said first-mentioned bafile. 

